| 1. |
- Hallingbäck, Henrik, et al.
(författare)
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Optimal timing of early genetic selection for sawn timber traits in Picea abies
- 2018
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Ingår i: European Journal of Forest Research. - : Springer. - 1612-4669 .- 1612-4677. ; 137:4, s. 553-564
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Tidskriftsartikel (refereegranskat)abstract
- In breeding Norway spruce, selection for improved growth and survival is performed at age 10-15 years in order to optimize genetic gain per year. We investigated whether a selection based on wood traits such as density and grain angle, measured under bark in the field at the same age would be informative enough with respect to structural quality traits of sawn boards. To achieve this objective, a sawing study was conducted on the butt logs of 401 trees from a 34-year-old Norway spruce progeny trial situated in southern Sweden. Stem discs were excised from the top of the logs and radial profile data of grain angle, and wood density was recorded for specific annual rings. The sawn and dried boards were assessed for structural traits such as twist, board density, bending stiffness (static modulus of elasticity, sMoE) and bending strength (modulus of rupture, MoR). Additive genetic correlations (r (a)) between single annual ring density measurements and board density, sMoE and MoR were consistently strong (r (a)> 0.7) for annual rings 5-13. Genetic correlations of similar magnitude between grain angle and board twist were estimated for all investigated annual rings (from 2 to around 26 under bark). Consequently, it was found that indirect selection for wood density and grain angle at the tree age 10-16 years would result in more genetic gain per year than selection at later ages. This makes it feasible to perform simultaneous selection of progeny in the field for both growth and wood traits at similar ages.
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| 2. |
- Dicksved, Johan, et al.
(författare)
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Fecal microbiome of growing pigs fed a cereal based diet including chicory (Cichorium intybus L.) or ribwort (Plantago lanceolata L.) forage
- 2015
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Ingår i: Journal of Animal Science and Biotechnology. - : Springer Science and Business Media LLC. - 1674-9782 .- 2049-1891. ; 6
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Tidskriftsartikel (refereegranskat)abstract
- Background: The purpose of this study was to investigate how inclusion of chicory forage or ribwort forage in a cereal-based diet influenced the fecal microbial community (microbiome) in newly weaned (35 days of age) piglets. The piglets were fed a cereal-based diet without (B) and with inclusion (80 and 160 g/kg air-dry forage) of vegetative shoots of chicory (C) and leaves of ribwort (R) forage in a 35-day growth trial. Fecal samples were collected at the start (D0), 17 (D17) and 35 (D35) days after weaning and profiles of the microbial consortia were generated using terminal restriction fragment length polymorphism (T-RFLP). 454-FLX pyrosequencing of 16S rRNA gene amplicons was used to analyze the microbial composition in a subset of the samples already analyzed with T-RFLP.Results: The microbial clustering pattern was primarily dependent on age of the pigs, but diet effects could also be observed. Lactobacilli and enterobacteria were more abundant at D0, whereas the genera Streptococcus, Treponema, Clostridium, Clostridiaceae1 and Coprococcus were present in higher abundances at D35. Pigs fed ribwort had an increased abundance of sequences classified as Treponema and a reduction in lactobacilli. However, the abundance of Prevotellaceae increased with age in on both the chicory and the ribwort diet. Moreover, there were significant correlations between the abundance of Bacteroides and the digested amount of galactose, uronic acids and total non-starch polysaccharides, and between the abundance of Bacteroidales and the digested amount of xylose.Conclusion: This study demonstrated that both chicory and ribwort inclusion in the diet of newly weaned pigs influenced the composition of the fecal microbiota and that digestion of specific dietary components was correlated with species composition of the microbiota. Moreover, this study showed that the gut will be exposed to a dramatic shift in the microbial community structure several weeks after weaning.
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| 3. |
- Edenius, Lars, et al.
(författare)
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Referensområden som verktyg för viltförvaltningsunderlag
- 2019
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Ingår i: Fakta. Skog. - 1400-7789.
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Annan publikation (populärvet., debatt m.m.)abstract
- Referensområden är områden där vi följer populationer av älg och andra viltarter, samt förändringar i landskapet, mer intensivt.Referensområden är viktiga för att utveckla övervakningsmetoder och skaffa sig bra kunskap om hur systemet fungerar, för utbildning, samt som demonstrationsområden.Referensområden förväntas bli en viktig komponent i den nya ekosystembaserade viltförvaltningen.Slaktvikter, reproduktionsdata, åldersstruktur, älgtäthet, fodermängder, betestryck och skogsskador är exempel på data som är relevanta att samla in i referensområden för den nya älgförvaltningens behov.SLU har flera områden och försöksparker som kan utvecklas till nationella referensområden.Fördjupad övervakning inom referensområden är ett viktigt komplement till förvaltningsinventeringar inom miljöanalys och viltövervakning.
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| 4. |
- Jarnemo, Anders, et al.
(författare)
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Temporal variations in activity patterns during rut - Implications for survey techniques of red deer, Cervus elaphus
- 2017
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Ingår i: Wildlife research (East Melbourne). - Clayton : CSIRO Publishing. - 1035-3712 .- 1448-5494. ; 44:2, s. 106-113
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Tidskriftsartikel (refereegranskat)abstract
- Context Intraspecific differences in behaviour can affect censuses and bias population estimates, suggesting that choice and implementation of census methods are fundamental, and need to be adapted to behavioural variations. Aims We investigated temporal variations in activity patterns during the rut among red deer (Cervus elaphus) categories and the implications for two different census methods. Methods We used a long-term dataset collected during 17 consecutive red deer rutting seasons in southernmost Sweden. The two census methods were: (1) a collection of observation ratios; and (2) a count of individuals including identification of males. Both methods are commonly used in ungulate management. Key results There was a difference in activity among age and sex categories, with a temporal variation in activity and/or presence at rutting grounds of adult (≥6 years) and subadult (2-5 years) males. Observation ratios of adult and subadult males increased from low at the start of the rut to a top level during peak rut, with subadults lagging behind adults. Before and during peak rut, the proportion of adult males was higher than that of subadults. After peak rut, the proportion of adult males decreased, whereas subadult males remained high, resulting in a higher number of subadults than of adults. The comparison of the two census methods revealed a strong correlation regarding the trends of population size and for the age and sex categories. There was also a strong consistency concerning the calf/female ratio. The male proportion was, however, consistently lower in the collected observations than in the counts. Conclusions The lower proportion of males in observations compared with counts may be explained by behavioural differences among male age classes, i.e. by temporal variations in presence and activity. That females, calves and yearling males are stationary during the rut, but adult and subadult males arrive and depart the rutting grounds at varying points of time, can lead to an underestimated male proportion in continuously collected observation data. Implications The results suggest that census should be conducted during peak rut, and that incorporating identification of individual males in the monitoring may be beneficiary. © CSIRO 2017.
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| 5. |
- Martis, Mihaela-Maria, et al.
(författare)
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RNA-Seqde novo assembly and differential transcriptome analysis of the nematode Ascaridia galli in relation to in vivo exposure to flubendazole
- 2017
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Ingår i: PLOS ONE. - : PUBLIC LIBRARY SCIENCE. - 1932-6203. ; 12:11
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Tidskriftsartikel (refereegranskat)abstract
- The nematode Ascaridia galli (order Ascaridida) is an economically important intestinal parasite responsible for increased food consumption, reduced performance and elevated mortality in commercial poultry production. This roundworm is an emerging problem in several European countries on farms with laying hens, as a consequence of the recent European Union (EU) ban on conventional battery cages. As infection is associated with slow development of low levels of acquired protective immunity, parasite control relies on repeated use of dewormers (anthelmintics). Benzimidazoles (BZ) are currently the only anthelmintic registered in the EU for use in controlling A. galli and there is an obvious risk of overuse of one drug class, selecting for resistance. Thus we developed a reference transcriptome of A. galli to investigate the response in gene expression before and after exposure to the BZ drug flubendazole (FLBZ). Transcriptional variations between treated and untreated A. galli showed that transcripts annotated as mitochondrial glutamate dehydrogenase and cytochrome P450 were significantly down-regulated in treated worms, whereas transcripts homologous to heat shock proteins (HSP), catalase, phosphofructokinase, and a multidrug resistance Pglycoprotein (PGP1) were significantly up-regulated in treated worms. Investigation of candidate transcripts responsible for anthelmintic resistance in livestock nematodes led to identification of several tubulins, including six new isoforms of beta-tubulin, and several ligandgated ionotropic receptors and ABC-transporters. We discovered several transcripts associated with drug binding and processing genes, but further characterisation using a larger set of worms exposed to BZs in functional assays is required to determine how these are involved in drug binding and metabolism.
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| 6. |
- Patching, Geoffrey, et al.
(författare)
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A new method of random environmental walking for assessing behavioral preferences for different lighting applications
- 2017
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Ingår i: Frontiers in Psychology. - : Frontiers Media SA. - 1664-1078. ; 8:345
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Tidskriftsartikel (refereegranskat)abstract
- Accurate assessment of people’s preferences for different outdoor lighting applications is increasingly considered important in the development of new urban environments. Here a new method of random environmental walking is proposed to complement current methods of assessing urban lighting applications, such as self-report questionnaires. The procedure involves participants repeatedly walking between different lighting applications by random selection of a lighting application and preferred choice or by random selection of a lighting application alone. In this manner, participants are exposed to all lighting applications of interest more than once and participants’ preferences for the different lighting applications are reflected in the number of times they walk to each lighting application. On the basis of an initial simulation study, to explore the feasibility of this approach, a comprehensive field test was undertaken. The field test included random environmental walking and collection of participants’ subjective ratings of perceived pleasantness, perceived quality, perceived strength, and perceived flicker of 4 lighting applications. The results indicate that random environmental walking can reveal participants’ preferences for different lighting applications that, in the present study, conformed to participants’ ratings of perceived pleasantness and quality of the lighting applications. As a complement to subjectively stated environmental preferences, random environmental walking has the potential to expose behavioral preferences for different lighting applications.
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| 7. |
- Tarbiat, Behdad, et al.
(författare)
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Comparison between anthelmintic treatment strategies against Ascaridia galli in commercial laying hens
- 2016
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Ingår i: Veterinary Parasitology. - : Elsevier BV. - 0304-4017 .- 1873-2550. ; 226, s. 109-115
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Tidskriftsartikel (refereegranskat)abstract
- The efficacy of a sustainable deworming strategy based on targeted treatments (TT) against Ascaridia galli was investigated for the first time in laying hen flocks on a Swedish commercial farm. Three experimental protocols with different levels of treatment, e.g. targeted treatment (TT), conventional treatment (CT) and untreated (UT), were tested in randomly allocated flocks of two different bird hybrids. Every second week faecal egg counts (FECs) were determined from pooled faecal materials collected on trays (20 x 27 cm) placed for a maximum of 12 h on the litter belts. In the TT, anthelmintic administration (fenbendazole, 1 mg/kg body weight for 5 days) started at 22 weeks post placement (wpp) and was repeated twice when the pooled FECs surpassed the assigned threshold of 200 egg per gram faeces (EPG). The CT flocks were treated once at 27 wpp using the same anthelmintic. Hens in the UT were not dewormed and served as controls. Additionally, FECs on cloacal contents, worm fecundity and worm burdens were determined at 19, 35 and 45 wpp. None of the flocks became infected until after 16 wpp. The cumulative pooled FECs at the end of the study were significantly (p < 0.01) lower in the TT compared to both CT and UT. Although repeated treatment in the TT protocol did not affect the fecundity, a worm density-dependent increase in fecundity was observed. Cloacal FECs and the number of adult A. galli in TT at 35 and 45 wpp were significantly lower compared to other flocks. This study provides evidence that the TT strategy is better in terms of lower worm burden and decreased cumulative environmental parasite egg numbers compared to CT strategy. The TT strategy should be considered as an alternative to the CT strategy with regard to A. galli control in commercial laying hens. (C) 2016 Elsevier B.V. All rights reserved.
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| 8. |
- Tarbiat, Behdad, et al.
(författare)
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Developmental capacity of Ascaridia galli eggs is preserved after anaerobic storage in faeces
- 2018
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Ingår i: Veterinary Parasitology. - : Elsevier BV. - 0304-4017 .- 1873-2550. ; 255, s. 38-42
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Tidskriftsartikel (refereegranskat)abstract
- The reliability of the results of in vitro studies such as detection of anthelmintic resistance often depends on the ability of the parasite eggs to develop under laboratory conditions. The aim of this study was to assess the embryonation capability of the chicken roundworm Ascaridia galli eggs after storage under different conditions. Two storage media for parasite eggs were used; faeces or water. Eggs in petri dishes (90 dishes in total) containing faces or water media were first exposed either to aerobic or anaerobic conditions at different temperatures (4 degrees C / + O-2, 4 degrees C / -O-2, 25 degrees C / -O-2) for a maximum of 72 days. Every second week, materials from petri dishes in triplicates were recovered and incubated aerobically for two weeks at 25 degrees C. After the incubation, 200-300 eggs from each petri shish (sampling unit) were counted and the number of embryonated eggs was determined. Data was analyzed in R (version 3.4.3) A logistic regression model with the probability of an egg to embryonate as dependent variable and conditions, storage medium and time points as fixed effects with quasibinomial distribution was run. Least-square means were calculated and pairwise comparisons were made with the fixed effect factors (condition, storage medium and time point). Eggs in faeces had a significantly (p < 0.05) higher embryonation than those in water, irrespective of storage conditions. At 4 degrees C embryonation tended to decline over time under aerobic conditions irrespective of the storage medium, whereas it remained constant following storage at anaerobic conditions. In contrast, anaerobic storage at the 25 degrees C negatively affected egg development in both media, except for day 14 in faeces. Our major finding was that eggs in faeces under anaerobic conditions and at 4 degrees C retained the highest rate of development, with a minimum decline in their developmental capacity over time compared to cleaned eggs stored in water.
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| 9. |
- Tarbiat, Behdad, et al.
(författare)
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Evaluation of benzimidazole resistance status in Ascaridia galli
- 2017
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Ingår i: Parasitology. - 0031-1820 .- 1469-8161. ; 144, s. 1338-1345
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Tidskriftsartikel (refereegranskat)abstract
- Susceptability of Ascaridia galli to benzimidazole (BZ) was investigated using faecal egg count reduction test (FECRT), in ovo larval development test (LDT) and genetic markers (mutations at codons 167, 198 and 200 of beta-tubulin gene). Six flocks (F1-F6) of a commercial laying hen farm with different number of exposure to BZ were recruited. The FECR was calculated by analyzing individual faeces (F1, F2, F4 and F5) before and 10 days after treatment. The LDT was performed on parasite eggs from pooled samples from F1 to F6 and LC50 and LC99 were calculated. DNA was extracted from 120 worms and sequenced for beta-tubulin gene. In all flocks, the FECRs were above 95% (lower CI above 90%). No significant difference was observed (p > 0.05) among obtained LC50 (F1/F4 and F2/F5 vs F3/F6) in the LDT. However, LC50 and LC99 were higher than suggested values for declaration of resistance in other nematode species. No variation was observed in codon positions involved in BZ resistance. Overall, our results indicated lack of evidence of resistance to BZ in A. galli. More research is needed to confirm these results and to further optimize the existing tools for detection and monitoring of anthelmintic resistance in A. galli.
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| 10. |
- Tarbiat, Behdad, et al.
(författare)
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The efficacy of flubendazole against different developmental stages of the poultry roundworm Ascaridia galli in laying hens
- 2016
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Ingår i: Veterinary Parasitology. - : Elsevier BV. - 0304-4017 .- 1873-2550. ; 218, s. 66-72
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Tidskriftsartikel (refereegranskat)abstract
- Infection with the poultry roundworm Ascaridia galli has increased in European countries due to the ban on battery cages. This study was conducted in two commercial laying hen flocks (F1 & F2) on different farms in central Sweden. The aims were to (1) investigate the efficacy of flubendazole (FLBZ, 1.43 mg/kg administered in drinking water for 7 days) against adult and larval stages including histotrophic larvae of A. galli, and (2) determine how long it took before the flocks were reinfected after deworming. Accordingly, 180 randomly selected hens were sacrificed before drug administration (bd), on day 3 and 7 during drug administration (dd), and on a weekly basis for up to five weeks post drug administration (pd). Intestinal contents and cloacal materials of each hen plus pooled faecal samples from manure belts were investigated to assess the worm burden and the parasite egg per gram faeces (epg). Additionally, drinking water, and serum and gastrointestinal digesta content samples obtained from ten treated animals were analyzed by HPLC to measure FLBZ and its reduced (R-FLBZ) and hydrolyzed (H-FLBZ) metabolites. No parasite eggs were observed in cloacal samples on day 21 and 28 pd on F1 and on day 21 pd on F2. The epg in manure decreased by 65% and 88% on day 3 dd and by 99% and 97% on day 35 pd on F1 and F2 respectively. Mean FLBZ concentrations quantified in duodenal contents ranged between 0.50 and 0.79 mu g/g. Although, no histotrophic larvae were found dd, they reappeared one week pd (7 +/- 7 F1, 0.5 +/- 0.5 F2). Adult worms were found in both flocks before drug administration (44 +/- 20 F1, 35 +/- 25 F2), on day 3 dd (4 +/- 3 F1, 2 +/- 2 F2), and then not until day 35 (0.2 +/- 0.6) on Fl and day 28 (0.4 +/- 0.9) pd on F2. Thus, the only period in which no A. galli were found was on day 7 dd. Although FLBZ was highly efficient our results indicate that the birds were reinfected already within one week pd. (C) 2016 Elsevier B.V. All rights reserved.
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